Soon after the development of practical laser sources, laser beams have been used in industrial applications. Laser beams are currently used to induce refractive index changes in optical waveguide glass and particularly glass used in optical fibers. Index gratings are written into germano-silicate glass optical fibers with interference patterns formed by interfering ultraviolet laser beams. Periodic refractive index changes are induced by the interference pattern resulting in index gratings being formed or written in the fiber. Fiber Bragg gratings and long period fiber gratings are two examples of index gratings that are produced in optical fiber and are utilized in the transmission of optical telecommunication signals. Fiber Bragg gratings can be utilized as selective wavelength reflecting filters in the transmission of light through optical fibers. The spacing of the index gratings in the optical fiber is to provide for the reflection of a particular range of wavelengths while allowing other wavelengths to pass through the index grating without being reflected. The quality of previously produced Fiber Bragg gratings has been hindered by a high level of unwanted reflectivity sidelobes. Reflectivity sidelobes occur when wavelengths of light outside the intended high reflectivity wavelength band are reflected by the grating instead of being properly transmitted through the grating.